Tutorial - Repainting the Gryphon on a textured canvas

Nifor - Sybren - App Helmond

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Mosaizer Pro Tutorial Repainting the Gryphon on a textured canvas Here you learn how to paint on a canvas in several layers of paint. We will show how to use different brush sizes to make a ground‐layer, on which the following painting strokes add more detail and contribute to the photo‐realism. Finally, we will demonstrate how a surface texture is applied. Repainting the Gryphon on a textured canvas About textures In Mosaizer Pro, textures are bitmap pictures of a textured surface. Each picture is a photo‐copy of e.g. burlap, jeans or wood. Texture bitmaps can easily be found on the internet. Just google and make a choice. The textures that we use are carefully selected from the heap of available texture bitmaps. First of all a texture needs to be photo‐realistic. Second, we want bitmaps of large pixel‐sizes to cover as much surface as possible in one go. Third, the texture bitmap should seamlessly be connected to each other to create larger surfaces without visible borders. The picture on the right shows a good texture (bottom) and a bad texture (top). And finally, we want good quality bitmaps where the compression artifacts (with jpg formats) or enlargement (when zoomed in) is hardly visible. A texture bitmap is applied as an additional layer over the picture and has a certain transparency. A typical surface texture has a transparency of appr. 15‐25% ...

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Publié par	Nifor
Nombre de lectures	15
Langue	Español

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MosaizerProTutorialRepaintingtheGryphononatexturedcanvas

Hereyoulearnhowtopaintonacanvasinseverallayersofpaint.Wewillshowhowtousedifferentbrushsizestomakeaground‐layer,onwhichthefollowingpaintingstrokesaddmoredetailandcontributetothephoto‐realism.Finally,wewilldemonstratehowasurfacetextureisapplied.

RepaintingtheGryphononatexturedcanvasAbouttexturesInMosaizerPro,texturesarebitmappicturesofatexturedsurface.Eachpictureisaphoto‐copyofe.g.burlap,jeansorwood.Texturebitmapscaneasilybefoundontheinternet.Justgoogleandmakeachoice.Thetexturesthatweusearecarefullyselectedfromtheheapofavailabletexturebitmaps.Firstofallatextureneedstobephoto‐ realistic.Second,wewantbitmapsoflargepixel‐sizestocoverasmuchsurfaceaspossibleinonego.Third,thetexturebitmapshouldseamlesslybeconnectedtoeachothertocreatelargersurfaceswithoutvisibleborders.Thepictureontherightshowsagoodtexture(bottom)andabadtexture(top).Andfinally,wewantgoodqualitybitmapswherethecompressionartifacts(withjpgformats)orenlargement(whenzoomedin)ishardlyvisible.Atexturebitmapisappliedasanadditionallayeroverthepictureandhasacertaintransparency.Atypicalsurfacetexturehasatransparencyofappr.15‐25%,andisusuallyslightlycolored(butblackandwhiteisfineaswell)toaddtotherealismeffect.RequirementsWeneedasourcepicture,severalbrushmasksandagoodqualitytexturebitmap.SinceMosaizerProhaspre‐installedbrush‐masksandtextures,wewillusethese.Alibraryofpicturesisnotrequiredbecausewenowusecoloredbrushstrokes,butit’savailableanywaybecausewithoutapicturelibraryMosaizerProdoesnotwork.ThestepstocreateaGryphononatexturedcanvasStep1:loadthesourcepictureandthebrushmaskThesourcepictureisloadedviaFile|Opensourcepicture(foralreadypreviouslyloadedsources)orbyaddinganewpictureviaFile|Newsourcepicture.Weusethepictureofthe1973album‘Gryphon’ofthegroupGryphon(e.g.viahttp://www.gaudela.net/gryphon/).Thebrushmaskwechooseistheb_WaxyCrayon.LoadthismaskasanalphamaskinthetabMasks.Step2:setthebasicpaintingparametersWhenpaintingwithbrushesitishighlyrecommendedtoplaywiththesettingsbeforefinallyrenderingafirstpicture.Wechangedthefollowingsettingsbeforewecreatedanymosaicpicture(withthesesettingsthetotalnumberofcellswillbe529):‐Colorbackgroundisactivatedandthecoloriswhite(viatabSpecial)‐Cellsizeissetto60px(isexplainedlater)

‐brushmasksareusuallyrotated,soactivatetheMaskrotate(viathetabQuicksettings|Othersettings);keepthestandardsettingsoftherotationangles(‐30to+30degrees)‐donotactivatetheMaskresize‐randomcellsplacementactivated(RandombuildandRandompatternboxesarechecked),1 selectarandomAmountof8 .‐IntheboxOverlaymask,selecttheColorizeoptionanditsvalueto8(slightlytransparent)ThenpresstheCreateorPreviewbuttontolookatthefirstrenderingeffect.Whydoweusealargebrushwhenalldetailsarenotreproducedverywell?Ourapproachisnotverystraightforwardcomparedwithotherphotomosaiccreations:wewillbuildthepicturefromlayersofpaintedsourcefiles.Eachtimewehaveanewresult,suchasthepictureontheright,wewillusethisasanewbackgroundonwhichwepaintthenextlayer.Witheachlayerwewilltakeasmallerbrushsize,withgrowingvisibilityofdetails,whilethebackgroundneedstobevisibleasafoundationofcolored‘specks’.Thiswayaverydynamicbrushsizerangeiscreated.Intermezzo:ashortlessononrandompatterns15000 Randompatternshaveagreatadvantage:thecellsthatareplacedonthecanvasseemtobe‘painted’withcertainrealism.Randombrush/strokepatternslook‘hand‐made’bydefinition.10000 Whenthecellsizeindecreased,morecellsaregeneratedtofillthe2 canvassurface.Thepictureontherightshowstherelationbetweencellsize(Hor.axis)andamountofcells(Vert.axis):large5000 cells(60px)generateabout800cellsonthecanvasarea,whilesmallcells(16px)generatemorethan12,000cellsonthecanvas.Whenonlythecellsizeischanged,thecanvassurfacecoverage0 remainsaboutconstant.0 2550 75 Therefore,tocreatealowercoveragetostillsee(partsof)thebackground,theAmountofrandompointsneedtodecrease.So,witheachnextlayerwenotonlyneedtodecreasethecellsize,butalsodecreasetheAmountofrandompoints.Step3:buildingthenextlayerFirst,youneedtoloadtheresultofthepreviousfullrenderingasthebackgroundpicture.AnewbackgroundpictureisloadedviaFile|Newbackgroundpictureandnavigatetotheresults

1 The value of theAmountslider is not visible in versions before Mosaizer Pro 7.0.33 2 This graph values are indicative and depend also on theAmountvalue and size of the source file

folderoftheMosaizerProapplication(orwhereveryouhavedefaultedtheresultpicture).BydefaultMosaizerProsavestheresultfileinthesubfolderResultsas<sourcepicturename>(Result).jpg.Incaseofdoubt,usetheWindowsexplorertolocalizethisresultpicture.Afterloading,alsocheckthisbackgroundpictureviathetabBackgroundintherighttopcorner.Next,chooseasmallerbrushsize(e.g.44px)anddecreasethecellcoverageviatherandomAmountsliderinthetabSpecial|Randomsettings.Wedecreasedthisvalueto6(totalnumberofpictures841).Thenrenderthepictureagain.Picture:thenextlayerontopofthefirstresult.Step4:built2morelayersRepeatstep3threemoretimes.Incaseyoudon’twanttokeeptheintermediateresults,simplyloadthenewbackgroundbyselectingthesamebackgroundagain.Thenewversionwillthenbeloaded.Incaseyouwanttokeeptheintermediateresults,youhavetomanuallyrenameandreloadthebackgroundpicturesagain.WeusedthefollowingsettingsforcellsizeandAmountofrandomcells:‐Cellsize=28pxwithAmount=4(totalamountofcells=1225)‐Cellsize=20pxwithAmount=2(totalamountofcells=1800)‐Cellsize=16pxwithAmount=1(totalamountofcells=2304)Forconveniencetheabovepictureshowsalltheseriesofallrenderingactionssofar(5layersintotal).Fromtoptobottomeachtimeanewbrushlayersisadded.Toppictureisthefirstrendering.Information:weused5stepstoexplaintheapproach.Inpractice3stepscoulddothejobaswell.Withmorelayers,theresultsfrom2or3layersbackwillprobablynotbevisibleagain.

Step5:applythesurfacetextureThecontrolsforthesurfacetexturesarefoundintwoplaces:inthe3Deffectstabthechoiceandsettingsarefound.InthetabColormatch|Transparencytheslidercanhelptoevaluatethebesttransparencysettingsaswell.Wefocusonthefirstcontrolbox:‐3Deffect:Texture‐Texture:thet_Burlap‐Transparency=80%‐Makethetextureblackandwhite(b/wboxischecked)‐Texturesize=1.0xDon’tchangetheothersettings,butsimplyre‐renderthelastlayer.Nowwehaveactivatedthesurfacetexture,therenderingenginewilladdanadditionalsteptotherenderingsequencebyaddingthistexturetotheresultingpicture.Theresultisshownatthefrontpageofthistutorial.VaryingthebrushmasksWhenthepictureisnowcompleted,it’stimetolookattheeffectofdifferentbrushes.Weshowtheresultsofthefinallayerrendering(incl.texture)offourdifferentbrushes.

FromLtoR:b_WaxyCrayon,b_Airbrush,b_Acrylic,b_Chalkandb_Chalkwith50%maskresizeTheinfluenceoftheAmountsettingsTheparametertocontrolthecoverageofthepaintistheAmountsliderintheRandomsettingstab.Thissliderdetermineshowmanyrandomcellpointsaregenerated.Seefigurebelow.

FromLtoR:Amount=0,3and5,withcellsize16px

Someotherpossiblevariations‐Brushmaskscanberotatedandresized.Trytoresizethebrush(inallsteps)andseetheeffectofcoverageandcolorimpression.‐Trytominimizetheamountoflayers.Wehaveusedfivelayers,butthreeisalsopossible.Tostillseethebackgroundofeachlayeryouneedtoexperimentwithcoverage(likeinthepicturebefore)andremembertherandomAmountsettings.‐VarytheColorizevalue(assetintheOverlaymaskcontrolbox).Wehaveusedavalueof8tocreateaslighttransparencyandtomixthestrokesofeachcellwiththeunderlyingstrokes.Asolidstroke(Colorize=10)willalsoresultagreateffects.‐DecreasetheColorizevaluefrome.g.from10via8downto6foreachlayer(3layers),whileatthesametimemanagethecoveragewiththerandomAmountvalue.Thiswaywitheachlayertransparencywillincrease(thusincreasinglyshowingthepreviouslayer).‐Useothertexturesandseetheeffect.Trycoloredtextures.